RGB to CMY - DMX Control

frank desben's icon

Dear all,
I have a Max Patch with RGB values that control the color of a light I control with DMX.
Now I have a different light model that uses CMY instead.
How do I calculate the CMY values based on the RGB values? It's possible, right?
Thanks for your help,
best, Frank

David Butler's icon

CMY is just inverted RGB.

C = 255 - R
M = 255 - G
Y = 255 - B

This assumes 8-bit colour for DMX. If you're using native max values for colour then replace 255 with 1.

Robert Dicken's icon

Um... that is wrong...

Roman Thilenius's icon

some would say it´s pretty correct. :)